Hello, I live by the freeway in the burbs of LA. My mindset was to always close the windows because of traffic smog. Since I got the AirGradient Indoor Monitor, keeping the windows would have a high CO2. If I open the windows, CO2 is good and oddly PMs are ok and so are the other parameters. Assuming this is a good thing and I can keep windows open within reason within the monitor readings? What have you all found in similar situations?
Thanks!
j
It might be counterintuitive, but today’s cars are actually quite clean in terms of PM from the exhaust. The regulations are very strict. In the US, a car is allowed to emit up to 1.9 mg of exhaust PM every kilometer it drives. This is low, considering that the initial limits from the last century were expressed in grams and not miligrams. The new cars (also diesel) are typically well-below the standard of 1.9 mg/km. In consequence, exhaust PM has drastically decreased in the US over the past decades. Today, scientists debate about the role of non-exhaust PM: airborne particles emitted from road, tyre, and brake abrasion. Several voices claim that non-exhaust particles became more relevant than tailpipe emissions, as a result of the decreased exhaust PM.
I am not surprised if your monitor does not see a lot of PM when you open the window. Note that this could change based on events such as wildfires and/or changes in wind direction.
Thanks for the response and excellent pts I never thought of